Dental Clinic May Have Exposed Kids to Deadly Bacteria 7 hospitalized after pulpotomies at Children's Dental Group By Arden Dier, Newser Staff Posted Sep 15, 2016 1:06 PM CDT 9 comments Comments A dentist works at Riley Hospital for Children's Department of Pediatric Dentistry in Indianapolis. (AP Photo/Michael Conroy) (Newser) – At least seven children have contracted a dangerous bacterial infection after a procedure at an Anaheim dental clinic—and 500 others could potentially have it, health officials say. Seven children have been hospitalized with oral cellulitis, an infection that can spread to gum and bone, after a routine pulpotomy or "baby root canal" at Children's Dental Group, reports the Orange County Register. Each patient developed abscesses that took up to six months to materialize, per CBS News. In one case, a 3-year-old boy had to undergo an operation to remove an abscess that was only detected after his teacher noticed his face was swollen. Oral cellulitis is typically eradicated with intravenous antibiotics or surgery but can be life-threatening. Officials suspect water used during the procedure may have been contaminated. They're now contacting 500 other children who had pulpotomies at the clinic since May. "I have not seen these types of cases in the 10 years that I've been here," says an official at the Orange County Health Care Agency. "It's very resistant to treatment and needs to be taken care of quickly." However, he says the risk of infection in other patients is low. Just 1% of patients became infected in a similar outbreak tied to pulpotomies at a Georgia clinic last year. The CEO of Children's Dental Group, which halted pulpotomies on Sept. 6, says "we follow industry standard sterilization and preventative practices … and are doing everything we can to resolve this."